Ground floor flooding

I've replaced the foundation of the house so I don't have water coming through the walls. When I did that I put in two sewer lines, one for waste and the other for rainwater. Still, I have had as much as an inch (when the sewer cap blew off) and have sandbags in place for under the door water when the water pushes out the outside drain and becomes a pool in the backyard. Without those, I would have an inch or so with every big storm. My neighbors have had as much as a foot of water and usually a few inches with each storm. You are probably right that they may have foundation leakage. The houses were built in 1905. I'm going to put a sump pump at the low point in the backyard. I have a check valve in the shower (but it doesn't entirely solve the problem in the shower).
We are downhill from the MTA bus depot which is a solid three square + blocks of asphault or buildings, so all of that drainage is headed strait at us. The businesses on 5th avenue are flooding too.
We've gone to DEP with little help and we're debating the next step to try to solve the issue. The community board knows about it.
If no one is responding to this post, I'm guessing this is a problem for the block more than the neighborhood.
Anyone know an engineer who could help us understand these issues? There are eight homeowners joining together to try to solve it. Any advice about the best approach to the politicians/ MTA would be appreciated.